Hydrogen production system and method for controlling the same

Abstract

A hydrogen production system and a method for controlling the same are provided. A renewable energy power generation system supplies electric energy to a hydrogen production device. The hydrogen production device discharges acceptable-purity hydrogen to the main hydrogen branch and discharges unacceptable-purity hydrogen to the mixed hydrogen branch. The mixed hydrogen branch receives high-purity hydrogen. The mixed hydrogen branch includes two valves to respectively control volumes of the high-purity hydrogen and the unacceptable-purity hydrogen flowing into the hydrogen mixing device in the mixed hydrogen branch, to control mixed hydrogen in the hydrogen mixing device to be the acceptable-purity hydrogen. The acceptable-purity hydrogen in the hydrogen mixing device is discharged to a purification branch in the main hydrogen branch, or a purification branch in the mixed hydrogen branch.

The invention claimed is: 
     
       1. A hydrogen production system, comprising:
 a renewable energy power generation system; 
 a hydrogen production device; 
 a main hydrogen branch; 
 a mixed hydrogen branch; and 
 at least one hydrogen storage device, wherein the renewable energy power generation system is configured to supply electric energy to the hydrogen production device for hydrogen production; 
 the hydrogen production device is configured to: discharge acceptable-purity hydrogen to a first gas inlet of the main hydrogen branch through a first gas outlet of the hydrogen production device; and discharge unacceptable-purity hydrogen to a first gas inlet of the mixed hydrogen branch through a second gas outlet of the hydrogen production device; 
 the mixed hydrogen branch is configured to receive high-purity hydrogen through a second gas inlet of the mixed hydrogen branch; 
 the mixed hydrogen branch comprises two valves, wherein one of the two valves is configured to control a volume of the high-purity hydrogen flowing into a hydrogen mixing device in the mixed hydrogen branch, and the other of the two valves is configured to control a volume of the unacceptable-purity hydrogen flowing into the hydrogen mixing device in the mixed hydrogen branch, to control mixed hydrogen in the hydrogen mixing device to be the acceptable-purity hydrogen; and 
 the at least one hydrogen storage device is configured to receive high-purity hydrogen from at least one of a purification branch in the main hydrogen branch or a purification branch in the mixed hydrogen branch, wherein the acceptable-purity hydrogen in the hydrogen mixing device is discharged to the purification branch in the main hydrogen branch, or the purification branch in the mixed hydrogen branch. 
 
     
     
       2. The hydrogen production system according to  claim 1 , wherein the mixed hydrogen branch further comprises a recycling branch and a feedback branch, wherein
 the two valves comprise a first valve and a second valve; 
 the hydrogen mixing device is a hydrogen mixing tank; 
 the hydrogen production device is configured to discharge the unacceptable-purity hydrogen to a first gas inlet of the hydrogen mixing tank through the second gas outlet of the hydrogen production device, the recycling branch and the first valve; 
 the feedback branch is configured to convey the high-purity hydrogen to a second gas inlet of the hydrogen mixing tank through the second valve; and 
 a gas outlet of the hydrogen mixing tank is in communication with a second gas inlet of the main hydrogen branch, wherein the acceptable-purity hydrogen discharged from the hydrogen mixing tank is purified in the purification branch in the main hydrogen branch. 
 
     
     
       3. The hydrogen production system according to  claim 2 , wherein the recycling branch comprises an unacceptable-purity hydrogen collection tank and a third valve, wherein
 the unacceptable-purity hydrogen collection tank is configured to receive the unacceptable-purity hydrogen through the third valve and a gas inlet of the unacceptable-purity hydrogen collection tank; and 
 a first gas outlet of the unacceptable-purity hydrogen collection tank is in communication with the first gas inlet of the hydrogen mixing tank through the first valve. 
 
     
     
       4. The hydrogen production system according to  claim 2 , wherein the feedback branch comprises a second hydrogen buffer tank and a fifth valve, wherein
 the second hydrogen buffer tank is configured to receive the high-purity hydrogen through a gas inlet of the second hydrogen buffer tank and the fifth valve; and 
 a gas outlet of the second hydrogen buffer tank is in communication with the second gas inlet of the hydrogen mixing tank through the second valve. 
 
     
     
       5. The hydrogen production system according to  claim 1 , wherein the mixed hydrogen branch further comprises a recycling branch, a feedback branch, a second hydrogen buffer tank, and a purification branch, wherein
 the two valves comprise a first valve and a fifth valve; 
 the second hydrogen buffer tank serves as the hydrogen mixing device; 
 the hydrogen production device is configured to discharge the unacceptable-purity hydrogen to a first gas inlet of the second hydrogen buffer tank through the second gas outlet of the hydrogen production device, the recycling branch and the first valve; 
 the feedback branch is configured to convey the high-purity hydrogen to a second gas inlet of the second hydrogen buffer tank through the fifth valve; and 
 the second hydrogen buffer tank is configured to discharge the acceptable-purity hydrogen through a gas outlet of the second hydrogen buffer tank, and the purification branch in the mixed hydrogen branch is configured to purify the acceptable-purity hydrogen discharged from the gas outlet of the second hydrogen buffer tank. 
 
     
     
       6. The hydrogen production system according to  claim 5 , wherein the recycling branch comprises a third valve, an unacceptable-purity hydrogen collection tank, a second hydrogen decompression unit, a second valve and a second one-way valve, wherein
 the unacceptable-purity hydrogen collection tank is configured to receive the unacceptable-purity hydrogen through the third valve and a gas inlet of the unacceptable-purity hydrogen collection tank; 
 a first gas outlet of the unacceptable-purity hydrogen collection tank is in communication with a gas inlet of the second hydrogen decompression unit through the first valve; and 
 a gas outlet of the second hydrogen decompression unit is in communication with the first gas inlet of the second hydrogen buffer tank through the second valve and the second one-way valve. 
 
     
     
       7. The hydrogen production system according to  claim 2 , wherein
 a hydrogen purity analyzer is provided in the hydrogen mixing device; and 
 the first valve is controlled based on a measurement result of the hydrogen purity analyzer. 
 
     
     
       8. The hydrogen production system according to  claim 3 , wherein
 a hydrogen purity analyzer is arranged in the unacceptable-purity hydrogen collection tank; and 
 the unacceptable-purity hydrogen collection tank is configured to discharge hydrogen out of the hydrogen production system through a second gas outlet of the unacceptable-purity hydrogen collection tank and a safety valve. 
 
     
     
       9. The hydrogen production system according to  claim 3 , wherein a hydrogen purity analyzer is arranged in the hydrogen production device, wherein
 the third valve is controlled based on a measurement result of the hydrogen purity analyzer in the hydrogen production device; and 
 the hydrogen production device is configured to discharge hydrogen out of the hydrogen production system through a third gas outlet of the hydrogen production device. 
 
     
     
       10. The hydrogen production system according to  claim 4 , wherein the feedback branch further comprises a first hydrogen decompression unit and a fourth valve, wherein
 the second hydrogen buffer tank is configured to receive the high-purity hydrogen from the main hydrogen branch through the fourth valve, the first hydrogen decompression unit and the fifth valve. 
 
     
     
       11. The hydrogen production system according to  claim 4 , wherein
 a sixth valve is arranged between the at least one hydrogen storage device and a gas outlet of the main hydrogen branch. 
 
     
     
       12. The hydrogen production system according to  claim 5 , wherein the purification branch in the mixed hydrogen branch comprises an eleventh valve, a second hydrogen purification device, a tenth valve and a third one-way valve, wherein
 a gas inlet of the second hydrogen purification device is in communication with the gas outlet of the second hydrogen buffer tank through the eleventh valve; and 
 a gas outlet of the second hydrogen purification device is in communication with a gas inlet of one of the at least one hydrogen storage device through the tenth valve and the third one-way valve. 
 
     
     
       13. The hydrogen production system according to  claim 2 , wherein the main hydrogen branch comprises a seventh valve, a first hydrogen buffer tank, an eighth valve, a first hydrogen purification device and a ninth valve, wherein
 a gas inlet of the seventh valve serves as the first gas inlet of the main hydrogen branch; 
 a first gas inlet of the first hydrogen buffer tank is in communication with a gas outlet of the seventh valve; 
 a gas outlet of the first hydrogen buffer tank is in communication with a gas inlet of the first hydrogen purification device through the eighth valve; 
 a second gas inlet of the first hydrogen buffer tank serves as the second gas inlet of the main hydrogen branch; and 
 a gas outlet of the first hydrogen purification device is in communication with a gas inlet of one of the at least one hydrogen storage device through the ninth valve. 
 
     
     
       14. The hydrogen production system according to  claim 5 , wherein the main hydrogen branch comprises a seventh valve, a first hydrogen buffer tank, an eighth valve, a first hydrogen purification device, a ninth valve and a first one-way valve, wherein
 a gas inlet of the seventh valve serves as the first gas inlet of the main hydrogen branch; 
 a first gas inlet of the first hydrogen buffer tank is in communication with a gas outlet of the seventh valve; 
 a gas outlet of the first hydrogen buffer tank is in communication with a gas inlet of the first hydrogen purification device through the eighth valve; and 
 the first hydrogen purification device is configured to discharge the high-purity hydrogen through a gas outlet of the first hydrogen purification device, and the gas outlet of the first hydrogen purification device is in communication with a gas inlet of one of the at least one hydrogen storage device through the ninth valve and the first one-way valve. 
 
     
     
       15. A method for controlling a hydrogen production system, wherein the method is applied to the hydrogen production system according to  claim 1 , and the method comprises:
 receiving high-purity hydrogen and unacceptable-purity hydrogen by a hydrogen mixing device in a mixed hydrogen branch of the hydrogen production system; 
 determining whether hydrogen in the hydrogen mixing device meets requirements of acceptable-purity hydrogen; 
 stopping receiving the unacceptable-purity hydrogen by the hydrogen mixing device when the hydrogen in the hydrogen mixing device meets the requirements of the acceptable-purity hydrogen; and 
 stopping receiving the high-purity hydrogen by the hydrogen mixing device. 
 
     
     
       16. The method for controlling a hydrogen production system according to  claim 15 , wherein
 the stopping receiving the unacceptable-purity hydrogen and the stopping receiving the high-purity hydrogen are performed simultaneously; or 
 the stopping receiving the unacceptable-purity hydrogen is performed a preset time period earlier than the stopping receiving the high-purity hydrogen is performed. 
 
     
     
       17. The method for controlling a hydrogen production system according to  claim 15 , wherein, after the stopping receiving the high-purity hydrogen, the method further comprises:
 discharging, when a pressure of the hydrogen in the hydrogen mixing device is stable, the hydrogen from the hydrogen mixing device to a gas inlet of the purification branch in the main hydrogen branch of the hydrogen production system, or to a gas inlet of the purification branch in the mixed hydrogen branch. 
 
     
     
       18. The method for controlling a hydrogen production system according to  claim 15 , wherein a hydrogen purity analyzer is arranged in a hydrogen production device of the hydrogen production system, wherein
 the method further comprises: discharging, in a case that hydrogen in the hydrogen production device is the acceptable-purity hydrogen, the acceptable-purity hydrogen from the hydrogen production device to the main hydrogen branch of the hydrogen production system through a first gas outlet of the hydrogen production device; and 
 before receiving high-purity hydrogen and unacceptable-purity hydrogen by the hydrogen mixing device in the mixed hydrogen branch of the hydrogen production system, the method further comprises: discharging, in a case that the hydrogen in the hydrogen production device is the unacceptable-purity hydrogen, the unacceptable-purity hydrogen from the hydrogen production device to a recycling branch of the hydrogen production system through a second gas outlet of the hydrogen production device. 
 
     
     
       19. The method for controlling a hydrogen production system according to  claim 18 , further comprising:
 discharging, in a case that the concentration of the hydrogen in the hydrogen production device is less than a preset unacceptable-purity hydrogen concentration, the hydrogen out of the hydrogen production system through a third gas outlet of the hydrogen production device. 
 
     
     
       20. The method for controlling a hydrogen production system according to  claim 17 , wherein a hydrogen purity analyzer is arranged in an unacceptable-purity hydrogen collection tank of a recycling branch of the hydrogen production system, wherein after the unacceptable-purity hydrogen collection tank receives the hydrogen, the method further comprises:
 discharging, in a case that concentration of the hydrogen in the unacceptable-purity hydrogen collection tank is less than a preset unacceptable-purity hydrogen concentration, the hydrogen in the unacceptable-purity hydrogen collection tank out of the hydrogen production system through a second gas outlet of the unacceptable-purity hydrogen collection tank; and 
 discharging, in a case that concentration of the hydrogen in the unacceptable-purity hydrogen collection tank is greater than or equal to the preset unacceptable-purity hydrogen concentration, the hydrogen in the unacceptable-purity hydrogen collection tank through a first gas outlet of the unacceptable-purity hydrogen collection tank and a first valve of the hydrogen production system to a first gas inlet of the hydrogen mixing device.